Eudonia mercurella


Eudonia mercurella belongs to the family Crambidae which includes the so called Grass Moths. This is a large Family with 140+ species recorded in Britain alone.

Eudonia mercurella


A small moth with a 16-19mm wingspan(1). Can be difficult to identify and a good ID book such as (2) below is recommended. It is single brooded and flies June-Sep (2).

It’s place in the Garden (Possible Resident)

The larva/caterpillars feed on mosses, of which a few species are present in the Garden, including one species known to be a food plant, see below.

Eudonia mercurella

All stages of a moths development are subject to a wide range of predators. Including small mammals, birds and amphibians. Other invertebrates are also a major threat, including dragonflies, beetles, lacewing and wasps. As such whilst many view certain caterpillars as a pest, these small packets of protein help support a wide array of other beneficial and interesting species. Moths are of course interesting in their own right and are very welcome in the Garden.

How to encourage the species to your garden

Current distribution maps (2) show this species to be common across Britain, but less so in Scotland. Mosses are more common in some gardens than others and the only species we have named for this moth is Hypnum compressiforme and Homalothecium sericum. The latter species H.sericum is common in the Garden and in many gardens where conditions are right. We find it on our stone steps and is otherwise known as Silky Wall Feather Moss. Therefore it is possibly this species of moth is resident.

Alternatively, you can lure moths to you by leaving a secure window open and a light on during the warmer months, or better still invest in a moth trap. Even if you don’t see this species, you may be visited by many other interesting species.

  1. UK Moths: Species Account Page. – Accessed online 21st December 2022
  2. Sterling, P & Parsons, M (2012): Bloomsbury Wildlife Guides: Field Guide to the Micro moths of Great Britain and Ireland. Bloomsbury Publishing Ltd